Abstract:

Barcode scanner including a multitasking pattern mirror which allows the
size of a scanner to be reduced without decreasing performance. The bar
code scanner includes a laser for producing a laser beam, a mirrored
spinner for reflecting the laser beam, and a plurality of pattern mirrors
for directing the laser beam from the mirrored spinner to produce a scan
pattern and for directing light reflected from an item to the mirrored
spinner. One of the pattern mirrors is located between the laser and the
mirrored spinner and includes an aperture for allowing the laser beam to
pass through. The one pattern mirror may also serve to direct the
reflected light from the mirrored spinner to the collector.

Claims:

1. A bar code scanner comprising:a laser for producing a laser beam;a
mirrored spinner for reflecting the laser beam; anda plurality of pattern
mirrors for directing the laser beam from the mirrored spinner to produce
a scan pattern and for directing light reflected from an item to the
mirrored spinner;wherein one of the pattern mirrors is located between
the laser and the mirrored spinner and includes an aperture for allowing
the laser beam to pass through.

2. The bar code scanner of claim 1, further comprising:a collector for
collecting the reflected light from the item; anda detector for
converting the reflected light received from the collector into
electrical signals;wherein the one pattern mirror directs the reflected
light from the mirrored spinner to the collector.

3. The bar code scanner of claim 2, further comprising:an additional
mirror adjacent to and coplanar with the one pattern mirror for directing
a portion of the reflected light from the mirrored spinner to the
collector.

4. A bar code scanner comprising:a housing including a window;a laser in
the housing for producing a laser beam;a mirrored spinner in the housing
for reflecting the laser beam and for reflecting reflected light from an
item;first and second groups of pattern mirrors in the housing;a
collector in the housing for collecting reflected light from the item;
anda detector in the housing for converting the reflected light into
electrical signals;wherein the first group of pattern mirrors directs the
laser beam from the mirrored spinner to the second group of pattern
mirrors and the second group of pattern mirrors directs the laser beam
through the window to produce a scan pattern for scanning the
item;wherein the second group of pattern mirrors directs the reflected
light from the item to the first group of pattern mirrors and the first
group of pattern mirrors directs the reflected light to the mirrored
spinner;wherein one pattern mirror of the first group of pattern mirrors
is located between the laser and the mirrored spinner and includes an
aperture for allowing the laser beam to pass through; andwherein the one
pattern mirror directs the reflected light from the mirrored spinner to
the collector.

5. The bar code scanner of claim 4, further comprising:an additional
mirror adjacent to and coplanar with the one pattern mirror for directing
a portion of the reflected light from the mirrored spinner to the
collector.

6. A scan method comprising:directing a laser beam through an aperture in
a first pattern mirror towards a mirrored spinner by a laser;reflecting
the laser beam towards the first pattern mirror and second pattern
mirrors by the mirrored spinner; anddirecting the laser beam from the
mirrored spinner to produce a scan pattern for scanning an item bearing a
bar code label by the first pattern mirror and the second pattern
mirrors.

7. The method of claim 6, further comprising:receiving reflected light
from the item by the first pattern mirror and the second pattern
mirrors;directing the reflected light towards the mirrored spinner by the
first pattern mirror and the second pattern mirrors;directing the
reflected light towards the first pattern mirror by the mirrored
spinner;directing the reflected light towards a collector by the first
pattern mirror; anddirecting the reflected light towards a detector by
the collector.

8. The method of claim 7, further comprising:directing a portion of the
reflected light towards an additional mirror adjacent to and coplanar
with the first pattern mirror; anddirecting the portion of the reflected
light towards the collector by the additional mirror.

Description:

BACKGROUND

[0001]Barcode scanners are well known for their usefulness in retail
checkout and inventory control. They typically include a laser diode, a
mirrored spinner, a plurality of pattern mirrors, a collector, and a
detector. In particular, the function of the pattern mirrors is to direct
scanning beams from the mirrored spinner out of the scanner to form a
scan pattern. Furthermore, the pattern mirrors direct light reflected
from an item bearing a barcode label to the mirrored spinner.

[0002]In some applications, it is important to reduce size of barcode
scanners without decreasing performance.

SUMMARY

[0003]A barcode scanner including a multi-tasking pattern mirror is
provided.

[0004]The bar code scanner includes a laser for producing a laser beam, a
mirrored spinner for reflecting the laser beam, and a plurality of
pattern mirrors for directing the laser beam from the mirrored spinner to
produce a scan pattern and for directing light reflected from an item to
the mirrored spinner. One of the pattern mirrors is located between the
laser and the mirrored spinner and includes an aperture for allowing the
laser beam to pass through. The one pattern mirror may also serve to
direct the reflected light from the mirrored spinner to the collector.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005]FIG. 1 is a block diagram of a barcode scanner;

[0006]FIG. 2 is a view illustrating arrangement of pattern mirrors within
the barcode scanner;

[0019]Turning now to FIGS. 2-4, scanner 10 is illustrated in more detail.

[0020]In addition to multi-tasking pattern mirror 28, primary pattern
mirrors 24 include pattern mirrors 60a and 62a to one side of
multi-tasking pattern mirror 28, and pattern mirrors 60b and 62b to the
other side of multi-tasking pattern 28.

[0021]With reference to FIG. 3, scanner 10 includes housing 50 with window
52. Scanner 10 may be positioned for pass by scanning with window 52
oriented horizontally or vertically.

[0022]The optical design of scanner 10, including the use of multi-tasking
pattern mirror 28, facilitates a reduction in size of housing 50 from
conventional designs, particularly a reduction in depth D and length L.
The reduction may be as much as 50% in depth D and length L.

[0023]A further advantage is that optical scanner 10 produces 50% more
lines and line length compared to other single window scanners.

[0024]Laser beam 36 passes from one side of multi-tasking pattern mirror
28 to another through aperture 30 and strikes mirrored spinner 16.
Without aperture 30, primary pattern mirrors 24 would have to be located
farther from mirrored spinner 16 to avoid obstructing laser beam 36 on
its way to mirrored spinner 16, thereby increasing the depth D and length
L of scanner 10.

[0025]Mirrored spinner 16 sweeps laser beam 36 across primary pattern
mirrors 60a, 62a, 28, 62b, and 60b. In an example embodiment, mirrored
spinner 16 includes five facets 38. Each facet 38 is oriented at a
slightly different angle in order to shift each scan line between five
different positions in the scan volume above window 52.